


Buried Deep Underwater

by superwholockwhatidk



Series: Canon-Compliant Destiel [2]
Category: Supernatural
Genre: Angst, Canon Compliant, Casifer, Destiel - Freeform, Episode: s11e14 The Vessel, M/M, Pining, Protectiveness, Time Travel, happy ending (ish), posession
Language: English
Status: Completed
Published: 2016-02-27
Updated: 2016-02-27
Packaged: 2018-05-23 14:26:54
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,190
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6119245
Author URL: https://archiveofourown.org/users/superwholockwhatidk/pseuds/superwholockwhatidk
Summary: <blockquote class="userstuff">
              <p>How Cas and Dean reacted to the events of 11x14 The Vessel through thoughts, emotions and actions not shown in the show. Lots of angst and protectiveness.</p>
            </blockquote>





	Buried Deep Underwater

It’s not too bad having to listen to Lucifer talking to Crowley. Castiel has to say, the torturing was not pleasant. Watching anyone stripped of their dignity and will to live is in no way ‘fun’. But it is far less aggravating than the ‘fake Cas’ voice Lucifer puts on every time he talks to Dean. 

But Dean’s voice is still nice to listen to, almost making the painful imitation bearable. Until, inevitably, Lucifer sets himself on the path of the Winchesters. Which has Cas reawakening from the slumber he had lain in after the disaster of Lucifer’s last interaction with Dean. 

He’s been gathering himself in the back of his own head (which took some getting used to) and had tested the barriers holding him there. He’d figured out that while Lucifer was engaged in a particularly torturous activity (in the literal sense) it was easy to sneak round his defences, and see out of his own eyes for the first time in a while. 

Of course, to look was to gaze upon the face of another Crowley-supporting demon who was unlucky enough to announce their views in front of the fallen archangel. Their bloody faces weren’t easy to look at, even with the twisting form that came with being a demon, Lucifer did things that no being should ever experience when he had a person under his blade. 

But through it all he held onto the fact that every time he wrestled to look into the dark eyes of Lucifer’s latest victim he would be able to wrestle into a position of looking at Dean or Sam’s face. He would be able to take back control when it really mattered. And it seemed that that moment might be needed sooner than he imagined. 

He could feel Lucifer’s frustration when Sam, rightly, kept reinforcing that Castiel couldn’t time travel. Lucifer could, and Cas knew that he was teetering on the edge of revealing his identity. And Cas waited on tenterhooks, knowing that any great reveal would likely be followed by extreme violence, and probably death. And Castiel would most certainly have to try protect the Winchesters. 

But the trouble passes, and before Cas knows it he’s travelling through water, Dean beside him. And Cas takes a minute to appreciate the moment. 

It’s been a hell of a long time since Cas has zapped Dean anywhere. As Dean would say, the lack of flying has been since he lost his ‘angel mojo’. And Cas misses it. Because no matter how much Dean claimed to feel like vomiting his guts up in the aftermath of such travel he always looked so peaceful on the journey. Which is such a rarity for Dean Winchester. 

Of course Dean's journey happens in the blink of an eye, but Cas’ certainly don’t. and he feels himself experiencing happiness, even with Lucifer occupying his vessel. 

And that’s the time that Lucifer decides that Cas has seen enough. His vision of Dean and the water blurs. Castle briefly rebels before grudgingly giving his vision up. His strength will be much more important later on. Even though he might consider this sight as one that has made him the happiest he has had in a long time. 

But then Dean, even the feeling of his presence is gone, and Lucifer and him are tumbling in the ocean. In the panic of the moment Lucifer lets go, reverting back to the non-corporeal form he has occupied for so long, and Cas feels the water around him. It’s really cold. 

And then Lucifer is racing back to the bunker. Cas’ heart constricts with worry, because the generally peaceful surface of Lucifer’s grace is bubbling, like a hot spring about to shoot a geyser high into the sky. And the vague thought that Cas can scrape off the surface isn’t far from anger. Which in terms of Lucifer’s general self-restraint is as bad as him declaring war on all the known universe. So Castiel suits up for battle too, drawing his thoughts around him and feeling the thin, wavering light of his grace. 

***

When Cas arrives at the bunker, sopping wet, he has to admit that even he's a bit pissed off. Bouncing off the hull of a ship was not the most pleasant experience. But he's mostly pissed at himself.

Surely he could have kept a hold of Dean? If the Angel-proofed ship kept him out he could surely have zapped Dean back with him, it's not like the ship wanted him there. And Cas is all too aware that Dean's on a submarine with no backup. And even if all the backup Cas can offer comes in a Lucifer packaging he is still failing to be there for Dean. 

When Lucifer promised to not leave Dean alone Castiel made the same promise to Sam. Look how well that's worked out. 

As Sam natters on while Lucifer dries his hair Cas is all too aware of the archangel's ever shortening patience. He prays for Sam to shut up for a whole different reason to Lucifer.

He's almost relieved when Sam finds a spell that can get him away from the bunker for a legitimate reason. He’s relieved when Lucifer sets the spell up away from Sam, and his confusion, it would be too dangerous for Sam to realise who was really in his body. So when Cas hears footsteps approaching his heart sinks. It starts to sink even more as Sam questions in a way that can only lead to the truth and as Lucifer’s impatience grows. 

“You’re not strong enough, Cas. You could get hurt.” At Sam’s words Cas glows just a bit. It’s generally a sign that something is majorly wrong if the Winchesters start to worry about him, but it’s appreciation that he exists, none the less. 

“You find a better option?” Lucifer gets out through gritted teeth. Cas is roughly jerked back to reality. 

“Well…No, but without a serious boost to your angel power, that spell won’t even work.” 

“My strength may surprise you.” 

Castiel relaxes at Sam’s lack of response and watches as Lucifer goes back to chopping the ingredients for the spell. Cas even stops straining himself in an attempt to see the surroundings with clarity. But Sam doesn’t walk away. 

“Wait a second. I remember Bobby told me, when you needed strength to retrieve us from the past, you used him to power up. You-“ there is a pause, and Cas readies himself for the inevitable fallout, “-you touched his soul. Right?” 

Cas holds his breath (figuratively), and waits for Lucifer’s reply, making an effort to see the world around him in piercing clarity. 

Cas listens to the conversation, all the while waiting for the pin to drop, and remembering. He remembers back when Sam even had no soul, causing him pain was physically hurting him, his whole body seized up with the wrongness of that. He’d even taken a precious fifteen minutes out of fighting in the angelic civil war to recover. he remembers shaking, and clutching his precious few photographs of the winchesters, smiling and relatively happy, in his hand. And if the pain of Sam’s torture wasn’t enough there was Dean’s expression. So of course Castiel is shocked and horrified at a repeat experience. 

“Use my soul.” 

Castiel feels the annoyance dissipate from Lucifers grace, and something else starts to fester. Something potentially even more dangerous. Disbelief, impatience and, worst of all, happiness. 

And then Lucifer starts laughing. Cas feels the act of trying to be like him drop from the frame of the body he’s squashed into. And when Lucifers, and it’s most certainly Lucifer’s, voice breaks out laughing from his vessel that’s when he truly starts to panic. And of course panicking means that his control slips. His vision slips and a red fog descends over his vision, as Lucifer almost stretches inside the vessel, asserting his personality. And Cas feels violated all over again. 

With all the blockage and confusion, added to Castiel’s frankly distraught state of mind it isn’t surprising that the conversation continues in fragments. And that only serves to disorient him more. 

“I don’t need you any more.” Cas hears, and he gathers his forces. 

Cas feels something snap inside the shitstorm that is Lucifer's brain. And then he's pushed, forcibly, to the very back of the headspace he had available. He can feel the crushing weight of Lucifer's consciousness but he can still hear Sam's voice. So he hears it when Sam starts to scream. 

As Lucifer slips past the point of causing pain and towards Sam's eventual death Cas gingerly extends a tendril of grace, knowing that Lucifer could incinerate it with a thought. 

But it holds, and then Cas has his legs back. His grace expands, folding out of a hole that it was crammed into. Then Lucifer starts to fight back. Lucifer is an archangel, but Castiel is a seraph. He can at least try to fight. And then, with a final burst of strength he falls into place. 

It’s awkward, and consumes his strength, but his hand, HIS hand, is retracted from Sam. 

“Sam, it’s me.” Cas chokes out through shuddering lips. A brief vacation in the back of his head hasn’t done any wonders for his people skills, clearly. 

“Cas? Why?” Sam says, and the disbelief and almost accusation in Sam’s voice makes Lucifer nearly halt his train of thought, giving way to Lucifer. It nearly makes him question his choices to be here. Because Sam’s moral compass is nearly always right, so if he thinks cas is in the wrong, there must be something going on. 

But Cas pushes his doubts away and struggles to answer:

“I wanted to be of service to the fight. And only Lucifer can beat her.” 

“You chose this?” Sam asks, and Cas falters again. “You have to fight, Cas. Eject him now!” 

But even as Cas sways towards Sam’s argument, his logic keeps him in his current situation. 

“I can’t. It’s taking all my strength to keep him from killing you. And besides, we need him.” 

And then his lips are gone. He manages to keep Lucifer from talking, throwing a cover of light over the bubbling red of his grace. But it’s only temporary. he blacks out of what Sam says next, and when he does come back - breathing heavily - it takes the last dregs of his strength. 

“We need him to save Dean.” Cas gets out, highlighting the whole cause of this. 

Because Cas would be up for trying to eject himself from Lucifer, maybe with a bit more convincing. Maybe Amara could be stopped another way. But Dean is, or was, on a submarine that is doomed to sink. And his only hope is Lucifer. And Cas will gladly give up his freedom to prevent Dean perishing at the bottom of an ocean.

So eventually he lets go. 

***

When Dean hears Sam’s frantic words - “That’s not Cas!” - his first thought is not of Lucifer. It’s of Cas, being left behind on that submarine. Because Dean hated being boxed in that submarine, second only to travelling via plane. So Cas dying down there was not an option. 

Eventually he flinches away from not cas’ hand on his shoulder, that he definitely hadn’t been leaning into. Nope. And he could pretend that it’s just his body that hurts when he’s thrown across the room. But it’s Cas, and he just hurt him. So of course he’s entitled to a little pain. Even though it literally feels like his heart is being ripped out. 

Even when Sam, later, tells him that Cas is possibly still in the vessel Lucifer is occupying it doesn’t help. Dean feels like curling into a ball with several bottles of whiskey and just staying in the bunker to wait for whatever it is to blow over. Because Cas is gone, and he same to have taken most of the hope of winning this fight with him. The only thing that stops him from clutching his painful chest is Sam. He can’t, won’t, show weakness in front of him. 

But then Sam drops a bigger bombshell and Dean feels too numb to even let a tear escape. 

“Like I said, Lucifer may be in control now, but Cas may not come back willingly. I mean, he chose it.” 

“No. no, not possible.” Is what come’s out of Dean’s mouth. But inside, oh god, inside he needs it not to be true. 

That Cas chose to side with Lucifer is one thing, but it proves that he doesn’t believe in them. That he doesn’t believe in Dean. And that’s what really makes Dean want to stick a gun in his mouth at the end of the day. 

However, what Dean doesn’t know is that even as Cas is nearly eradicated in the small part of Lucifer’s mind he previously occupied the thought he is hanging onto is that he managed to save Dean Winchester. And that Dean will be coming to save him. Because Cas does believe in Dean, more than Dean would ever let himself think.

**Author's Note:**

> Thank you for reading! Please comment with opinions and prompts.


End file.
